Whats App is most common useful app now a days.Almost everyone has this app in their mobile phone.It is because it has lots of useful features.First feature is that we can send unlimited messages if we have internet connection.Secondly, we can send videos and voice messages to unlimited users.Moreover, its registration is so easy.It assists us to make friends very easy.We can send anything through this app.It is very very useful.So, we should use it instead of making call to anyone. It is very easy to use.It takes very few seconds to send a single message to our friend or relatives or to any other person.It is great app.